This invention relates to a plastic binding device of the type to be used on a joint in a hose for the purpose of ensuring safe union of the two joined ends or on a plurality of electric cables or pipes for the purpose of tightly bundling them together.
Numerous binding devices have been developed to date for such purposes. By material, they can be grouped under two categories: those made of metals and those made of plastics. Generally, when a hose is attached to the cock of a gas or water pipe or to the inlet or outlet of a radiator in an automobile, for example, a binding device which incorporates a metal band capable of providing relatively high binding force is preferably used around the terminal portion of the hose for the purpose of ensuring perfect union of the hose to the cock or to the inlet or outlet. For the purpose of binding a plurality of electric cables, etc. into a tight bundle, a plastic binding device incorporating a plastic band which enjoys low cost and high moldability is adopted.
A binding device made of plastic material which is inexpensive, easy to mold, resistant to corrosion and capable of providing high binding strength will find utility in various applications without reference to the type of objects on which the binding device is to be used.
From this point of view, it is seen that ordinary conventional plastic binding devices comprise a band adapted to be wrapped around the article subjected to binding such as hoses, electric cables and pipes, and a fastening member. One end of the band is generally attached integrally to the fastening member. On the other hand, the fastening member is provided with a fastening hole for permitting insertion of the other end, namely the free end, of the band. Inside the fastening hole is disposed a check claw or some other suitable fastening means adapted to be engaged with a complementary fastening member disposed on the band side. Such is the construction found in most conventional binding devices.
To increase the force with which the band is wrapped around the article, after the band has been wound around the article, inserted through the fastening hole and allowed to protrude from the opposite side of the fastening hole, the worker is required to firmly grasp the free protruding end of the band with his finger tips or a suitable tool and give it a forceful pull. The work of pulling, by nature, is such that the manner in which the force is exerted upon the free end of the band cannot be accurately adjusted as one wishes. Thus, some allowance must be given to the increase of force which is actually effected on the band. Apart from the problem of the fastening force (binding force), the workability of the fastening device itself which relies upon such manual pulling does not prove to be highly desirable. Particularly in a limited space, this work of pulling is found to be extremely difficult.
The object of this invention is to provide a plastic binding device which readily provides necessary binding force and permits the binding work to be accomplished with ease.